Installation

•Do not start the motor more than six times per hour. Short cycling the tower will cause fuses, breakers or O.L.s to operate and will decrease motor life.

When using a two-speedstarter:

 

• Motor rotation must be the same at slow speed and high speed.

 

• Single winding motor requires a starter with a shorting contactor.

 

•

Two-winding motor requires a starter with out a shorting

 

 

contactor.

 

•

All two-speed starters must have a 20 second time delay relay

 

 

when switching from high speed to low speed.

 

•

Do not start the motor more than six times per hour (each low

 

 

speed start and each high speed start count as one start).

 

When using a VFD:

 

Before beginning, ensure that the motor is rated for “Inverter Duty”

Note

per NEMA MG-1, part 31.

 

 

•

Set the VFD solid state overload protection to 119% of motor

 

 

nameplate amps and set “maximum current parameter” in the

 

 

VFD to motor nameplate amps. “Maximum current parameter” will

 

 

reduce fan speed and limit amp draw to nameplate amps during

 

 

cold weather operation. If furnished with a mechanical O.L. set this

 

 

at 110% over motor nameplate amps.

 

• Motor rotation must be the same in both VFD mode and By-pass

 

 

mode.

 

• If cable distance between the VFD and motor is greater than 31m

 

 

feet a DV/DT output filter is recommended to avoid damage to the

 

 

motor. 31mº distance is based on our field experience, the VFD

 

 

manufacture may state different distances and distance does vary

 

 

depending on the VFD manufacture.

• Program the VFD for variable torque output. Flux vector and con- stant torque modes may damage the gearbox.

• Do not start and stop the motor using the safety switch at the motor. If the drive is being commanded to run and the load side is cycled ON and OFF with the safety switch this may damage the VFD.

Using a VFD in cooling applications has advantages over traditional single or two speed motor control. A VFD can reduce the cost of electrical en- ergy being used and provide better temperature control. In addition, it reduces the mechanical and electrical stress on the motor and mechanical

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SPX Cooling Technologies MHF702, MHF705 user manual When using a two-speedstarter, When using a VFD
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MHF702, MHF705 specifications

SPX Cooling Technologies has established itself as a leader in innovative cooling solutions, with the MHF705 and MHF702 units being prime examples of their commitment to efficiency and performance. These models are designed specifically for cooling processes in various industrial applications, providing reliable operation while minimizing energy consumption.

The MHF705 and MHF702 units are both equipped with advanced features that enhance their operational efficiency. One of the standout characteristics is their modular design, which allows for easy customization and scalability according to the system requirements. This flexibility makes them suitable for a wide range of applications, from HVAC systems to industrial cooling processes.

In terms of technology, both units utilize SPX’s proprietary air distribution system that optimizes airflow patterns within the unit. This ensures uniform cooling and reduces hot spots, contributing to enhanced overall performance. Additionally, the MHF series incorporates high-efficiency fans designed to reduce energy consumption while maximizing cooling output. These fans not only operate quietly but also have extended lifespans, reducing the need for frequent replacements.

Another significant feature of the MHF705 and MHF702 models is their robust construction. With materials designed to withstand harsh environmental conditions, including corrosion-resistant coatings, these units promise longevity and durability. This resilience is crucial for industries where reliability and minimal downtime are paramount.

The MHF series also excels in terms of maintainability. Features such as easily accessible components and modular serviceability make routine maintenance straightforward, which helps in limiting operational interruptions. Additionally, the units are designed with energy efficiency in mind, complying with various environmental standards, which reflects SPX's commitment to sustainability.

Both models also benefit from advanced control technologies, allowing for seamless integration with existing systems. Users can monitor and adjust settings easily via a user-friendly interface, ensuring optimal performance tailored to specific cooling demands.

In summary, SPX Cooling Technologies’ MHF705 and MHF702 units represent the pinnacle of modern cooling technology. With their advanced features, scalable design, high durability, and energy-efficient operation, these cooling solutions stand out as ideal choices for a diverse range of industrial applications, ensuring that businesses can rely on them for efficient and dependable cooling performance.
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